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arXiv · 2209.02245

A topometric Effros theorem

Itaï Ben Yaacov·Julien Melleray
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Abstract

Given a continuous and isometric action of a Polish group $G$ on an adequate Polish topometric space $(X,\tau,\rho)$ and $x \in X$, we find a necessary and sufficient condition for $\overline{Gx}^\rho$ to be co-meagre; we also obtain a criterion that characterizes when such a point exists. This work completes a criterion established in earlier work of the authors.

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Itaï Ben Yaacov, Julien Melleray. 2022-09-06. A topometric Effros theorem. https://arxiv.org/abs/2209.02245

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